Lightning is an electrostatic discharge between electrically charged regions within clouds or between a cloud and the surface of a planet. There are four primary types of lightning: intra-cloud lightning, cloud-to-cloud lightning, cloud-to-air lightning, and cloud-to-ground lightning. Cloud-to-cloud lightning is prevalent at the beginning of thunderstorms. Lightning detection systems, in combination with weather radar, are utilized by meteorological services to locate and track thunderstorms.
There are three primary types of lightning detection systems: ground-based systems utilizing multiple detectors, mobile detection systems (often aboard an aircraft), and space-based systems. Each type of lightning detection system has its own limitations. Because mobile detection systems utilize attenuation rather than triangulation to determine lightning location, mobile detection systems may have difficulty discerning whether a weak lightning strike is nearby or a strong lightning strike is far away. Because space-based lightning detection systems take more time to disseminate information than mobile or ground-based systems, information from space-based lightning detection systems is of limited value for real-time applications such as air navigation.
Meteorological services such as the U.S. National Weather Service utilize ground-based lightning detection systems, which utilize triangulation from multiple detectors in multiple locations to determine the location of lightning strikes. The National Lightning Detection Network (NLDN), for example, includes approximately 100 ground-based detectors located across the continental United States. Those detectors sense the electromagnetic signals of a lightning strike and transmit the data via a satellite to a central processing location in Tucson. Ariz., which estimates the location of the lightning strike by triangulating three or more signals.
Conventional ground-based lightning detection systems also suffer from a number of drawbacks. The most significant drawback is a lack of accuracy due to the limited number of ground-based detectors. Because ground-based lightning detectors may be hundreds of miles away, the accuracy of even the most advanced ground-based lightning detection systems is limited.
Detecting cloud-to-cloud lightning with conventional ground-based detection systems is particularly difficult because one detector may detect the location of lightning on the starting cloud and another detector may detect the location of lightning on the receiving cloud. In order to detect and locate cloud-to-cloud lightning within an acceptable margin of error, ground-based lightning detection systems require at least three detectors within the detection range. Because the number of ground-based lightning detectors is limited, conventional ground-based lightning detection systems underestimate cloud-to-cloud lightning. Conventional ground-based lightning detectors have similar drawbacks when detecting clout-to-air lightning.
The accuracy of conventional ground-based lightning detection networks may be improved by increasing the number of ground-based detectors. However, the cost of the network is increased each time a ground-based detector is manufactured, deployed, and maintained. Accordingly, there is a need for a lightning detection network with improved accuracy while minimizing the cost of manufacturing, deploying, and maintaining the ground-based detectors.